TSI Rankings | Applications

All trophic status rankings are conducted by ecoregion and
expressed as a percentile. In general, as trophic state
increases, moving from oligotrophy to eutrophy
(e.g., phosphorus and chlorophyll increase and Secchi
transparency decreases), percentile ranking decreases.

Glossary Term Category

General Glossary

Glossary Term Show In Main

Yes

Glossary Term Ext Def

For example, a Carlson TSI of 37 (phosphorus concentration
of 10 ppb) corresponds to the 90th percentile in the Northern
Lakes and Forests (<A HREF="#table1">Table 1</a>). In other
words, this TSI (concentration) is lower than 90 percent of the
assessed lakes in this ecoregion. In contrast, a TSI of 60
(phosphorus concentration of 50 ppb) would rank at the 10th
percentile for the Northern Lakes and Forests which implies that
this TSI (concentration) is lower than ten percent of the
assessed lakes (or inversely, higher than 90 percent).
The percentile ranking should be evaluated relative to the number
of lakes assessed in the ecoregion (<A HREF="#table1">Table
1</A>). For example, in the Northern Lakes and Forest ecoregion,
phosphorus TSI values (concentrations) are available for 804
lakes (<A HREF="#table1">Table 1</A>). If new TSI values are
calculated for a lake (e.g., based on
more recent data than this assessment), a new ranking for the
lake may be estimated from <A HREF="#table1">Table 1</A>. A
statewide ranking, based on this data set, is also included.

<A NAME="table1"></A>Table 1. Minnesota Lake Water Quality
Data
Base Summary (1998). Distribution of Carlson TSI values
and
lake basin morphometry measurements by ecoregion (N = number
of
lakes). Percentiles

Northern Lakes and
Forests
<CENTER>
<TABLE WIDTH=600 BORDER=1 CELLPADDING=2 CELLSPACING=3>
<COL WIDTH=169>
<COL WIDTH=47>
<COL WIDTH=53>
<COL WIDTH=43>
<COL WIDTH=38>
<COL WIDTH=44>
<COL WIDTH=45>
<COL WIDTH=46>
<COL WIDTH=46>
<TR BGCOLOR="#ccccff">
<TD WIDTH=169>
Parameter / Percentile
</TD>
<TD WIDTH=47>
N
</TD>
<TD WIDTH=53>
95
</TD>
<TD WIDTH=43>
90
</TD>
<TD WIDTH=38>
75
</TD>
<TD WIDTH=44>
50
</TD>
<TD WIDTH=45>
25
</TD>
<TD WIDTH=46>
10
</TD>
<TD WIDTH=46>
5
</TD>
</TR>
<TR>
<TD WIDTH=169>
Area (acres)
</TD>
<TD WIDTH=47>
1,213
</TD>
<TD WIDTH=53>
18
</TD>
<TD WIDTH=43>
29
</TD>
<TD WIDTH=38>
71
</TD>
<TD WIDTH=44>
192
</TD>
<TD WIDTH=45>
448
</TD>
<TD WIDTH=46>
1,188
</TD>
<TD WIDTH=46>
2,173
</TD>
</TR>
<TR>
<TD WIDTH=169>
Depth, max. (feet)
</TD>
<TD WIDTH=47>
1,041
</TD>
<TD WIDTH=53>
10
</TD>
<TD WIDTH=43>
14
</TD>
<TD WIDTH=38>
22
</TD>
<TD WIDTH=44>
36
</TD>
<TD WIDTH=45>
57
</TD>
<TD WIDTH=46>
87
</TD>
<TD WIDTH=46>
112
</TD>
</TR>
<TR>
<TD WIDTH=169>
Depth, mean (feet)
</TD>
<TD WIDTH=47>
33
</TD>
<TD WIDTH=53>
4
</TD>
<TD WIDTH=43>
8
</TD>
<TD WIDTH=38>
14
</TD>
<TD WIDTH=44>
18
</TD>
<TD WIDTH=45>
24
</TD>
<TD WIDTH=46>
43
</TD>
<TD WIDTH=46>
49
</TD>
</TR>
<TR>
<TD WIDTH=169>
TSI-P
</TD>
<TD WIDTH=47>
804
</TD>
<TD WIDTH=53>
32
</TD>
<TD WIDTH=43>
36
</TD>
<TD WIDTH=38>
41
</TD>
<TD WIDTH=44>
47
</TD>
<TD WIDTH=45>
53
</TD>
<TD WIDTH=46>
58
</TD>
<TD WIDTH=46>
61
</TD>
</TR>
<TR>
<TD WIDTH=169>
TSI-Chla
</TD>
<TD WIDTH=47>
441
</TD>
<TD WIDTH=53>
32
</TD>
<TD WIDTH=43>
35
</TD>
<TD WIDTH=38>
39
</TD>
<TD WIDTH=44>
45
</TD>
<TD WIDTH=45>
50
</TD>
<TD WIDTH=46>
57
</TD>
<TD WIDTH=46>
61
</TD>
</TR>
<TR>
<TD WIDTH=169>
TSI-Secchi
</TD>
<TD WIDTH=47>
971
</TD>
<TD WIDTH=53>
34
</TD>
<TD WIDTH=43>
36
</TD>
<TD WIDTH=38>
39
</TD>
<TD WIDTH=44>
44
</TD>
<TD WIDTH=45>
49
</TD>
<TD WIDTH=46>
55
</TD>
<TD WIDTH=46>
59
</TD>
</TR>
<TR>
<TD WIDTH=169>
TSI-Mean
</TD>
<TD WIDTH=47>
1,223
</TD>
<TD WIDTH=53>
34
</TD>
<TD WIDTH=43>
36
</TD>
<TD WIDTH=38>
40
</TD>
<TD WIDTH=44>
45
</TD>
<TD WIDTH=45>
51
</TD>
<TD WIDTH=46>
55
</TD>
<TD WIDTH=46>
59
</TD>
</TR>
</TABLE>
</CENTER>
 North Central Hardwood
Forests

<CENTER>
<TABLE WIDTH=600 BORDER=1 CELLPADDING=2 CELLSPACING=3>
<COL WIDTH=167>
<COL WIDTH=48>
<COL WIDTH=51>
<COL WIDTH=44>
<COL WIDTH=35>
<COL WIDTH=50>
<COL WIDTH=46>
<COL WIDTH=45>
<COL WIDTH=45>
<TR BGCOLOR="#ccccff">
<TD WIDTH=167>
Parameter
</TD>
<TD WIDTH=48>
N
</TD>
<TD WIDTH=51>
95
</TD>
<TD WIDTH=44>
90
</TD>
<TD WIDTH=35>
75
</TD>
<TD WIDTH=50>
50
</TD>
<TD WIDTH=46>
25
</TD>
<TD WIDTH=45>
10
</TD>
<TD WIDTH=45>
5
</TD>
</TR>
<TR>
<TD WIDTH=167>
Area (acres)
</TD>
<TD WIDTH=48>
839
</TD>
<TD WIDTH=51>
18
</TD>
<TD WIDTH=44>
34
</TD>
<TD WIDTH=35>
73
</TD>
<TD WIDTH=50>
184
</TD>
<TD WIDTH=46>
444
</TD>
<TD WIDTH=45>
1,013
</TD>
<TD WIDTH=45>
1,924
</TD>
</TR>
<TR>
<TD WIDTH=167>
Depth, max. (feet)
</TD>
<TD WIDTH=48>
688
</TD>
<TD WIDTH=51>
8
</TD>
<TD WIDTH=44>
10
</TD>
<TD WIDTH=35>
19
</TD>
<TD WIDTH=50>
31
</TD>
<TD WIDTH=46>
48
</TD>
<TD WIDTH=45>
70

</TD>
<TD WIDTH=45>
83
</TD>
</TR>
<TR>
<TD WIDTH=167>
Depth, mean (feet)
</TD>
<TD WIDTH=48>
197
</TD>
<TD WIDTH=51>
5
</TD>
<TD WIDTH=44>
6
</TD>
<TD WIDTH=35>
10
</TD>
<TD WIDTH=50>
15
</TD>
<TD WIDTH=46>
21
</TD>
<TD WIDTH=45>
28
</TD>
<TD WIDTH=45>
31
</TD>
</TR>
<TR>
<TD WIDTH=167>
TSI-P
</TD>
<TD WIDTH=48>
604
</TD>
<TD WIDTH=51>
42
</TD>
<TD WIDTH=44>
45
</TD>
<TD WIDTH=35>
52
</TD>
<TD WIDTH=50>
61
</TD>
<TD WIDTH=46>
73
</TD>
<TD WIDTH=45>
82
</TD>
<TD WIDTH=45>
86
</TD>
</TR>
<TR>
<TD WIDTH=167>
TSI-Chla
</TD>
<TD WIDTH=48>
559
</TD>
<TD WIDTH=51>
42
</TD>
<TD WIDTH=44>
45
</TD>
<TD WIDTH=35>
50
</TD>
<TD WIDTH=50>
60
</TD>
<TD WIDTH=46>
69
</TD>
<TD WIDTH=45>
74
</TD>
<TD WIDTH=45>
77
</TD>
</TR>
<TR>
<TD WIDTH=167>
TSI-Secchi
</TD>
<TD WIDTH=48>
853
</TD>
<TD WIDTH=51>
39
</TD>
<TD WIDTH=44>
42
</TD>
<TD WIDTH=35>
46
</TD>
<TD WIDTH=50>
53
</TD>
<TD WIDTH=46>
60
</TD>
<TD WIDTH=45>
70
</TD>
<TD WIDTH=45>
73
</TD>
</TR>
<TR>
<TD WIDTH=167>
TSI-Mean
</TD>
<TD WIDTH=48>
877
</TD>
<TD WIDTH=51>
41
</TD>
<TD WIDTH=44>
44
</TD>
<TD WIDTH=35>
48
</TD>
<TD WIDTH=50>
56
</TD>
<TD WIDTH=46>
65
</TD>
<TD WIDTH=45>
73
</TD>
<TD WIDTH=45>
77
</TD>
</TR>
</TABLE>
</CENTER>
 Western Corn Belt
Plains
<CENTER>
<TABLE WIDTH=600 BORDER=1 CELLPADDING=2 CELLSPACING=3>
<COL WIDTH=166>
<COL WIDTH=46>
<COL WIDTH=52>
<COL WIDTH=46>
<COL WIDTH=43>
<COL WIDTH=42>
<COL WIDTH=47>
<COL WIDTH=45>
<COL WIDTH=45>
<TR BGCOLOR="#ccccff">
<TD WIDTH=166>
Parameter
</TD>
<TD WIDTH=46>
N
</TD>
<TD WIDTH=52>
95
</TD>
<TD WIDTH=46>
90
</TD>
<TD WIDTH=43>
75
</TD>
<TD WIDTH=42>
50
</TD>
<TD WIDTH=47>
25
</TD>
<TD WIDTH=45>
10
</TD>
<TD WIDTH=45>
5
</TD>
</TR>
<TR>
<TD WIDTH=166>
Area (acres)
</TD>
<TD WIDTH=46>
96

</TD>
<TD WIDTH=52>
42
</TD>
<TD WIDTH=46>
83
</TD>
<TD WIDTH=43>
178
</TD>
<TD WIDTH=42>
393
</TD>
<TD WIDTH=47>
711
</TD>
<TD WIDTH=45>
1,844
</TD>
<TD WIDTH=45>
2,900
</TD>
</TR>
<TR>
<TD WIDTH=166>
Depth, max. (feet)
</TD>
<TD WIDTH=46>
69
</TD>
<TD WIDTH=52>
3
</TD>
<TD WIDTH=46>
5
</TD>
<TD WIDTH=43>
7
</TD>
<TD WIDTH=42>
9
</TD>
<TD WIDTH=47>
14
</TD>
<TD WIDTH=45>
30

</TD>
<TD WIDTH=45>
48
</TD>
</TR>
<TR>
<TD WIDTH=166>
Depth, mean (feet)
</TD>
<TD WIDTH=46>
25
</TD>
<TD WIDTH=52>
4
</TD>
<TD WIDTH=46>
4
</TD>
<TD WIDTH=43>
5

</TD>
<TD WIDTH=42>
7
</TD>
<TD WIDTH=47>
10
</TD>
<TD WIDTH=45>
14
</TD>
<TD WIDTH=45>
15
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-P
</TD>
<TD WIDTH=46>
80
</TD>
<TD WIDTH=52>
63
</TD>
<TD WIDTH=46>
63
</TD>
<TD WIDTH=43>
71
</TD>
<TD WIDTH=42>
78
</TD>
<TD WIDTH=47>
82
</TD>
<TD WIDTH=45>
88
</TD>
<TD WIDTH=45>
92
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-Chla
</TD>
<TD WIDTH=46>
73
</TD>
<TD WIDTH=52>
55
</TD>
<TD WIDTH=46>
60
</TD>
<TD WIDTH=43>
64
</TD>
<TD WIDTH=42>
69
</TD>
<TD WIDTH=47>
74
</TD>
<TD WIDTH=45>
80
</TD>
<TD WIDTH=45>
81
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-Secchi
</TD>
<TD WIDTH=46>
99
</TD>
<TD WIDTH=52>
51
</TD>
<TD WIDTH=46>
54
</TD>
<TD WIDTH=43>
59
</TD>
<TD WIDTH=42>
70
</TD>
<TD WIDTH=47>
73
</TD>
<TD WIDTH=45>
77
</TD>
<TD WIDTH=45>
83
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-Mean
</TD>
<TD WIDTH=46>
101
</TD>
<TD WIDTH=52>
55
</TD>
<TD WIDTH=46>
60
</TD>
<TD WIDTH=43>
66
</TD>
<TD WIDTH=42>
71
</TD>
<TD WIDTH=47>
77
</TD>
<TD WIDTH=45>
81
</TD>
<TD WIDTH=45>
83
</TD>
</TR>
</TABLE>
</CENTER>
 Northern Glaciated
Plains
<CENTER>
<TABLE WIDTH=600 BORDER=1 CELLPADDING=2 CELLSPACING=3>
<COL WIDTH=166>
<COL WIDTH=49>
<COL WIDTH=47>
<COL WIDTH=48>
<COL WIDTH=41>
<COL WIDTH=39>
<COL WIDTH=33>
<COL WIDTH=54>
<COL WIDTH=55>
<TR BGCOLOR="#ccccff">
<TD WIDTH=166>
Parameter
</TD>
<TD WIDTH=49>
N
</TD>
<TD WIDTH=47>
95
</TD>
<TD WIDTH=48>
90
</TD>
<TD WIDTH=41>
75
</TD>
<TD WIDTH=39>
50
</TD>
<TD WIDTH=33>
25
</TD>
<TD WIDTH=54>
10
</TD>
<TD WIDTH=55>
5
</TD>
</TR>
<TR>
<TD WIDTH=166>
Area (acres)
</TD>
<TD WIDTH=49>
34
</TD>
<TD WIDTH=47>
77
</TD>
<TD WIDTH=48>
128
</TD>
<TD WIDTH=41>
164
</TD>
<TD WIDTH=39>
410
</TD>
<TD WIDTH=33>
995
</TD>
<TD WIDTH=54>
3,800
</TD>
<TD WIDTH=55>
11,528
</TD>
</TR>
<TR>
<TD WIDTH=166>
Depth, max. (feet)
</TD>
<TD WIDTH=49>
23
</TD>
<TD WIDTH=47>
5
</TD>
<TD WIDTH=48>
5
</TD>
<TD WIDTH=41>
7
</TD>
<TD WIDTH=39>
9
</TD>
<TD WIDTH=33>
14
</TD>
<TD WIDTH=54>
18
</TD>
<TD WIDTH=55>
25
</TD>
</TR>
<TR>
<TD WIDTH=166>
Depth, mean (feet)
</TD>
<TD WIDTH=49>
16
</TD>
<TD WIDTH=47>
4
</TD>
<TD WIDTH=48>
4
</TD>
<TD WIDTH=41>
5
</TD>
<TD WIDTH=39>
7
</TD>
<TD WIDTH=33>
8
</TD>
<TD WIDTH=54>
11
</TD>
<TD WIDTH=55>
11
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-P
</TD>
<TD WIDTH=49>
24
</TD>
<TD WIDTH=47>
58
</TD>
<TD WIDTH=48>
64
</TD>
<TD WIDTH=41>
74
</TD>
<TD WIDTH=39>
79
</TD>
<TD WIDTH=33>
87
</TD>
<TD WIDTH=54>
91
</TD>
<TD WIDTH=55>
92
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-Chla
</TD>
<TD WIDTH=49>
19
</TD>
<TD WIDTH=47>
44
</TD>
<TD WIDTH=48>
58
</TD>
<TD WIDTH=41>
62
</TD>
<TD WIDTH=39>
66
</TD>
<TD WIDTH=33>
69
</TD>
<TD WIDTH=54>
70
</TD>
<TD WIDTH=55>
72
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-Secchi
</TD>
<TD WIDTH=49>
33
</TD>
<TD WIDTH=47>
48
</TD>
<TD WIDTH=48>
52
</TD>
<TD WIDTH=41>
53
</TD>
<TD WIDTH=39>
65
</TD>
<TD WIDTH=33>
67
</TD>
<TD WIDTH=54>
73
</TD>
<TD WIDTH=55>
77
</TD>
</TR>
<TR>
<TD WIDTH=166>
TSI-Mean
</TD>
<TD WIDTH=49>
34
</TD>
<TD WIDTH=47>
56
</TD>
<TD WIDTH=48>
60
</TD>
<TD WIDTH=41>
65
</TD>
<TD WIDTH=39>
69
</TD>
<TD WIDTH=33>
72
</TD>
<TD WIDTH=54>
74
</TD>
<TD WIDTH=55>
81
</TD>
</TR>
</TABLE>
</CENTER>
 Statewide
<CENTER>
<TABLE WIDTH=600 BORDER=1 CELLPADDING=2 CELLSPACING=3
FRAME=RHS>
<COL WIDTH=0>
<COL WIDTH=161>
<COL WIDTH=46>
<COL WIDTH=50>
<COL WIDTH=47>
<COL WIDTH=43>
<COL WIDTH=40>
<COL WIDTH=43>
<COL WIDTH=44>
<COL WIDTH=54>
<TR>
<TD ROWSPAN=8 VALIGN=TOP></TD>
<TD WIDTH=161 BGCOLOR="#ccccff">
Parameter
</TD>
<TD WIDTH=46 BGCOLOR="#ccccff">
N
</TD>
<TD WIDTH=50 BGCOLOR="#ccccff">
95
</TD>
<TD WIDTH=47 BGCOLOR="#ccccff">
90
</TD>
<TD WIDTH=43 BGCOLOR="#ccccff">
75
</TD>
<TD WIDTH=40 BGCOLOR="#ccccff">
50
</TD>
<TD WIDTH=43 BGCOLOR="#ccccff">
25
</TD>
<TD WIDTH=44 BGCOLOR="#ccccff">
10
</TD>
<TD WIDTH=54 BGCOLOR="#ccccff">
5
</TD>
</TR>
<TR>
<TD WIDTH=161>
Area (acres)
</TD>
<TD WIDTH=46>
2,192
</TD>
<TD WIDTH=50>
18
</TD>
<TD WIDTH=47>
32
</TD>
<TD WIDTH=43>
76
</TD>
<TD WIDTH=40>
200
</TD>
<TD WIDTH=43>
472
</TD>
<TD WIDTH=44>
1,209
</TD>
<TD WIDTH=54>
2,243
</TD>
</TR>
<TR>
<TD WIDTH=161>
Depth, max. (feet)
</TD>
<TD WIDTH=46>
1,825
</TD>
<TD WIDTH=50>
7
</TD>
<TD WIDTH=47>
10
</TD>
<TD WIDTH=43>
19
</TD>
<TD WIDTH=40>
32
</TD>
<TD WIDTH=43>
52
</TD>
<TD WIDTH=44>
78
</TD>
<TD WIDTH=54>
98
</TD>
</TR>
<TR>
<TD WIDTH=161>
Depth, mean (feet)
</TD>
<TD WIDTH=46>
272
</TD>
<TD WIDTH=50>
4
</TD>
<TD WIDTH=47>
5
</TD>
<TD WIDTH=43>
8
</TD>
<TD WIDTH=40>
14
</TD>
<TD WIDTH=43>
20
</TD>
<TD WIDTH=44>
28
</TD>
<TD WIDTH=54>
33
</TD>
</TR>
<TR>
<TD WIDTH=161>
TSI-P
</TD>
<TD WIDTH=46>
1,519
</TD>
<TD WIDTH=50>
36
</TD>
<TD WIDTH=47>
39
</TD>
<TD WIDTH=43>
45
</TD>
<TD WIDTH=40>
53
</TD>
<TD WIDTH=43>
64
</TD>
<TD WIDTH=44>
77
</TD>
<TD WIDTH=54>
83
</TD>
</TR>
<TR>
<TD WIDTH=161>
TSI-Chla
</TD>
<TD WIDTH=46>
1,099
</TD>
<TD WIDTH=50>
36
</TD>
<TD WIDTH=47>
39
</TD>
<TD WIDTH=43>
45
</TD>
<TD WIDTH=40>
53
</TD>
<TD WIDTH=43>
64
</TD>
<TD WIDTH=44>
72
</TD>
<TD WIDTH=54>
76
</TD>
</TR>
<TR>
<TD WIDTH=161>
TSI-Secchi
</TD>
<TD WIDTH=46>
1,966
</TD>
<TD WIDTH=50>
35
</TD>
<TD WIDTH=47>
38
</TD>
<TD WIDTH=43>
42
</TD>
<TD WIDTH=40>
49
</TD>
<TD WIDTH=43>
56
</TD>
<TD WIDTH=44>
65
</TD>
<TD WIDTH=54>
73
</TD>
</TR>
<TR>
<TD WIDTH=161>
TSI-Mean
</TD>
<TD WIDTH=46>
2,245
</TD>
<TD WIDTH=50>
36
</TD>
<TD WIDTH=47>
38
</TD>
<TD WIDTH=43>
43
</TD>
<TD WIDTH=40>
49
</TD>
<TD WIDTH=43>
59
</TD>
<TD WIDTH=44>
70
</TD>
<TD WIDTH=54>
75
</TD>
</TR>
</TABLE>
</CENTER>
 If the individual TSI values for a lake do not
correspond fairly closely (e.g., within 5 TSI units), then the
individual values should be inspected and particular attention
should
be paid to the number of observations used to calculate the mean
values and to determine which parameter might be the more
accurate
predictor of trophic state. The following notes may be helpful in
this regard:

a. If one index value is based on numerous measures while the
others are based on a single measure, then the former is probably
the
better indicator of trophic state.
b. If there is only a single measurement for each index value,
the
phosphorus TSI should be favored as it provides an estimate of
the
"potential" trophic status of a lake.
c. Secchi or chlorophyll-a TSIs based on single observations
should be viewed with caution.
d. Secchi TSI values in highly colored waters (see note 4) or
waters high in inorganic suspended solids (e.g., clay) may
provide a
poor estimate of trophic state. This is because the dark
coloration
or high suspended sediments may limit the amount of algae
produced
and often will be the primary factor limiting transparency.
<IMG
SRC="http://www.pca.state.mn.us/artwork/water/aphanizomenon.jpg"
NAME="Graphic12" ALT="Aphanizomenon" ALIGN=RIGHT HSPACE=5
WIDTH=300 HEIGHT=216 BORDER=0>e.
Lakes dominated by large colonial algae, such as Aphanizomenon
sp.
(look like clumps of grass clippings), may have high
transparencies
(low TSI) relative to the phosphorus concentration. This is
because
these colonies of algae may form "rafts" or scums at
the
surface of the water which are easily displaced by wind or
lowering
of a Secchi disk and hence Secchi readings may be deeper than if
the
algae were dispersed evenly throughout the water column.
f. Lakes with extensive macrophyte (rooted submergent and
emergent
plants) growth may have higher transparency and lower
chlorophyll-a
(lower TSIs) than expected based on the phosphorus concentration.
These plants may compete with algae for available nutrients like
phosphorus.
g. Ecoregional patterns (i.e., percentile rankings) may also
give
an indication as to which TSI value is a better reflection of the
trophic status of a lake.
h. This data base may not provide an accurate estimate of the
current trophic status of a given lake because of the number of
observations or the age of the data. In particular, those labeled
as
"evaluated" should be viewed with caution since the
data
may be over ten years old.
i. If more current data is available for a lake, or if data is
available for a lake that is not included in the appendix, then
the
appendix data and Table 1 (i.e., TSIs and rankings) can be used
to
place the condition of the lake in perspective relative to other
lakes in a given ecoregion.